Click on link below for Amada Brochure with specifications:
https://www.amada.com/america/brochures/general-fabrication/ID40IV-HP-
NT/html5/index.html?&locale=ENG
These reduction bushes allow for the fitting of boring bars and drills with a tapered shaft. All sizes are manufactured in a range of capacities. The sleeves are hardened and ground for a good fit for both the holder and the shaft.